YouTube downloader?

Is there an app that I can download YouTube videos? I had an app on my windows phone that could do this, and the regular YouTube app doesn't do this. If you could let me know that would be great, thanks!

Google and YouTube no longer allows this. There is no app in the App Store that will download a video to your camera roll. I ran in to one last year and downloaded my own videos. I then deleted the app. Later it had been pulled from the App Store and was no longer in my purchased list. You can copy links. That's it, Apple will not allow an app to download from YouTube. There were copyright issues.